Bearingless pump



Feb. 25, 1964 R. s. BAKER ETAL BEARINGLESS PUMP 2 Sheets-Sheet 1 Filed Sept. 22, 1960 INVENTORS RICHARD S. BAKER BY IRWIN GOLDSTEIN W ATTORNEY 1964 R. s. BAKER ETAL BEARINGLESS PUMP 2 Sheets-Sheet 2 Filed Sept. 22, 1960 FIG.

IN VEN TORS RICHARD S. BAKER BY IRWIN GOLDSTEIN FIG. 4

ATTORNEY United States Patent 3,122,161 BEARINGLESS PUMP Richard S. Baker, Northridge, and Irwin Goldstein, Beverly Hills, Calii, assignors to North American Aviation, Inc.

Filed Sept. 22, 1960, Ser. No. 57,660 2 Claims. (Cl. 103--87) The present invention relates to pumps and more particularly to fluid pumps where the fluid forms the hearing support for rotation.

An object of the present invention is to minimize friction in a fluid pump by utilizing a boundary layer of the fluid purnped interposed between the moving surfaces.

Another object of the present invention is to provide a pump wherein no bearings are employed for supporting the pump rotor within the pump housing.

Another object of the present invention is to provide a pump in which high pressure areas are produced in the fluid pump between the rotor and the pump housing which maintain the rotor free of the housing during rotation.

A further object of the present invention is to provide a pump wherein the fluid supporting the rotor passes through the rotor to the housing surface thereby creating a high pressure boundary layer of fluid between the rotor and the housing, which layer supports the rotor.

These and other objects of the present invention will be more apparent from the following detailed description and drawings, hereby made a part hereof, in which:

FIGURE 1 is a partially sectioned view of the pump of the present invention;

FIGURE 2 is a section along line 22 of FIGURE 1;

FIGURE 3 is a partially sectioned plan view of the rotor; and

FIGURE 4 is an end vienv of the rotor of FIGURE 3.

The present invention provides a pump comprising a rotor, a housing surrounding the rotor and induction motor, inlet and outlet connections for the pump, and a means for supporting the rotor for rotation free of, and in spaced relation to, the housing by utilizing the pumped fluid as a support bearing.

Referring now to FIGURE 1, the preferred embodiment of the present invention is a pump having a housing having two frusta-conical sections 11 in axial alignment with end closures 12 and an inlet plenum 13 located therebetween. In et pipe 14 is connected between a source of fluid to be pumped (not shown) and the plenum 13. The housing 19 has a plurality of fluid outlet openings 15, erg, two along the axis 16 and two at the periphery adjacent the outer edge of the sections 11. These latter outlets are interconnected as at 17 with the axial outlets 15. Polyphase induction motor stators 18 are coaxialiy mounted on either side of the housing 10 to produce rotation by the reaction between a traveling magnetic field set up by the stator 18 and the eddy currents induced in the rotor 11?. The stator 18 is identical to the standard stator used in a disc-type induction motor, i.e. it consists of a steel structure having a plurality of radial slots in which the stator windings are placed, and therefore is not described in detail herein. The rotor 19 ha two conical end sections 25) and 21 with a spider support 22 interconnecting the sections in substantially parallel alignment with section 11. The rotor :19 is of reduced dimensions so that a clearance of about 0.050 inch between the rotor surface and the housing surface is present along the entire surface of rotor 19 during rotation of the rotor. The rotor 19 is shown in its operating position in FIGURE 1 and is located in contact with the bottom surface of the housing when stopped as is explained here inafter in the operation of the device.

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The rotor 19 (see FIGURE 2) is provided with a plurality of ports 23 along its entire surface and a plurality of vanes 24 each associated with a plurality of ports 23 along a line coplanar with the axis 16. The vanes 24 are partially cup shaped to direct fluid into and through the ports 25. Within each section 26 and 21 of the rotor is at least one impeller 25 (see FIGURE 3) having fixed blades which upon rotation cause fluid entering the pump to move toward the outlet 15, for example, through the copper rim 26 supported by copper hub 27 and spokes 28. Magnetic inserts 29 may be added to increase the driving force. In operation the pump causes the production of high pressure areas between the rotor 19 of the pump and the internal surfaces of the sections 11 of the housing 10. These high pressure areas maintain the rotor 19 clear of the interior surfaces. This is accomplished by directing a small part of the fluid by vanes 24 against opening 31) of ports 23 and through ports 23. The fluid passing through ports 23 causes a hydraulic pressure drop to be developed that causes the pressure at the in terior openings 30 of ports 23 to be greater than the pressure at the exterior openings 31 of the posts 23. In this manner the rotor 19 is maintained in spaced relation to and free of the housing 16 during operation without requiring conventional bearings.

During start-up the friction between the rotor 19 and the housing 19 may necessitate excessive power requirements for large pumps. Thus, if desirable, a start-up bearin surface 33 may be provided along the inside of housin 10 adjacent the inlet plenum 13 to reduce initial frictional losses. After rotation has created the boundary layer the rotor is freed from these surfaces 33.

The fluid passes through the inlet pipe 14 into the plenum 13 and through the apertures in spider support 22 to the volume within the conical sections 20 and 21. Rotation of the rotor 19 rotates the impellers 25 on each side of the support 22 which forces the fluid in opposite directions along a path parallel to the axis 16. Since the fluid movement is in opposite directions, the net resulting axial force on the rotor 19 is zero and no axial movement results, i.e., the pump is self-stabilizing in the axial direction. A part of the fluid moving within the rotor 19 is directed by vanes 24 through ports 23 to create a pressure drop which maintains the rotor 19 in spaced relation to housing 1%. Since the pressure drop created along the length of the conical section will be equal for each circular series of ports 23, the rotor is not only maintained in equally spaced relation with respect to the housing 14 but because of the axial vector component of this hydraulic force, the axial position is maintained. Thus in the preferred embodiment displacement in the axial direction as well as normal to the axis is at least partially controlled by the hydraulic pressure drop created by ports 23.

While conical rotor sections have been shown and are preferred, cylindrical rotor sections with stator windings concentric with the cylindrical rotor sections are the purview of the present invention. In such a modification axial position would be mm'ntained by the opposite forces on the impellers and not by any horizontal component of force of the boundary layer. Other modifications of the subject invention will be apparent to those skilled in the art, and therefore the invention is not limited to the specific embodiment described but only by the appended claims.

We claim:

1. A fluid pump comprising a housing, said housing having two sections, an inlet between said sections, axial outlets at the ends of said sections, a hollow rotor having two integral sections positioned within said housing and having a fluid inlet communicating with the interior of said rotor located between said rotor sections and adjacent said housing inlet, means for forcing fluid through each of said rotor sections in opposite directions from :said inlet to equalize axial forces, said means including means outside said housing for rotating said rotor, means for maintaining the position of said rotor in a direction normal to the axis of rotation of said rotor during the rotation thereof including ahigh pressure boundary layer of said fluid between said rotor sections and said housing sections. 7 V

2. A fluid pump comprising a housing having a fluid inlet and a plurality of fluid outlets, a hollow rotor positioned within said housing, said rotor having two axially symmetrical sections, said fluid inlet communicating with the hollow interior of said rotor between said two sections,

References Cited in the file of this patent FOREIGN PATENTS Great Britain May 17, 1938 Great Britain Nov. 1, 1946 

1. A FLUID PUMP COMPRISING A HOUSING, SAID HOUSING HAVING TWO SECTIONS, AN INLET BETWEEN SAID SECTIONS, AXIAL OUTLETS AT THE ENDS OF SAID SECTIONS, A HOLLOW ROTOR HAVING TWO INTEGRAL SECTIONS POSITIONED WITHIN SAID HOUSING AND HAVING A FLUID INLET COMMUNICATING WITH THE INTERIOR OF SAID ROTOR LOCATED BETWEEN SAID ROTOR SECTIONS AND ADJACENT SAID HOUSING INLET, MEANS FOR FORCING FLUID THROUGH EACH OF SAID ROTOR SECTIONS IN OPPOSITE DIRECTIONS FROM 